“(This increase-only model is also curiously similar to another theory, the second law of thermodynamics. It states that entropy - the progression from order to disorder in the Universe - can only increase. Black holes also have entropy ascribed to them, and it’s directly proportional to their event horizon surface area.)”
Black holes are not the Universe. Entropy can obviously decrease locally and temporarily, if energy pours into it. Consider the Earth and life on it.
Beyond that, I wonder what would happen to a positively charged black hole, if you started pouring electrons into it. Would the event horizon still grow?
The addition of electrons (which have a negative charge) to a positively-charged Black Hole would merely result in a gradual neutralization of the Black Hole's positive charge, while its total mass (and thus the area of its event horizon) would increase.
It has been established that a Black Hole can have only three different measurable (by an outside observer) properties: mass (measured by its gravitational field and size of event horizon); spin (measured by its oblateness); and electrical charge (which could be measured by bringing another charged body near it and measuring the repulsion / attraction).
But is there a limit to the amount of charge that a Black Hole could accumulate? Would the "internal pressure" that would build up if one were to continually add, say, only protons eventually elicit any unusual effect measurable by outside observers?
That's what I'd like to know.
Regards,
“Beyond that, I wonder what would happen to a positively charged black hole, if you started pouring electrons into it. Would the event horizon still grow?”
It should since it’s proportional to the mass and by adding electrons you’re increasing the mass.